迭代
class Solution {
public:
ListNode* mergeTwoLists(ListNode* l1, ListNode* l2) {
ListNode ans(0);
ListNode *p = &ans;
while(l1 && l2) {
if(l1->val < l2->val) {
p->next = new ListNode(l1->val);
p = p->next;
l1 = l1->next;
}else{
p->next = new ListNode(l2->val);
p = p->next;
l2 = l2->next;
}
}
while(l1) {
p->next = new ListNode(l1->val);
p = p->next;
l1 = l1->next;
}
while(l2) {
p->next = new ListNode(l2->val);
p = p->next;
l2 = l2->next;
}
return ans.next;
}
};
题目链接:https://leetcode-cn.com/problems/merge-two-sorted-lists/